Article

Beyond city limits

To meet the water demands of residents and businesses, cities around the world spend an estimated $90 billion annually on infrastructure to deliver and treat water. These systems can still fail us, and when they do, the economic costs extend beyond water treatment.

Written by Daniel Shemie

28th January 2015

For a week in early August, the people of Toledo, Ohio, dealt with the ultimate unsustainable situation: no clean water. The algal bloom in Lake Erie that cut off the city’s water supply for a full week meant no drinking from the tap, no bathing, no cooking, no cleaning, and no fishing or swimming in the lake. Toledo’s crisis was a wakeup call for the entire Great Lakes region, and yet another reminder to cities around the United States—we cannot take our water for granted.

Cleaning dirty water and transporting clean water vast distances comes at an enormous cost. To meet the water demands of residents and businesses, cities around the world spend an estimated $90 billion annually on infrastructure to deliver and treat water. These systems can still fail us, and when they do, the economic costs extend beyond water treatment. Algal blooms like Toledo’s are estimated to cost $2.2 billion a year in the United States [1].

Nature has an important role to play in water delivery and treatment, one that has gone largely untapped. A new report, “Urban Water Blueprint: Mapping Conservation Solutions to the Global Water Challenge,” from The Nature Conservancy, in partnership with C40 Cities Climate Leadership Group and the International Water Association, provides evidence about how protecting water at its source improves water quality and where it is most cost effective. The report includes findings on the water risk and conservation opportunity for over 200 cities in the United States.

Natural Return on Investment

New York, N.Y., famously showed that watershed protection can be cost-effective. In the 1990s, the city needed to demonstrate to state and federal regulators that it could comply with the Safe Drinking Water Act. In evaluating its options, the city discovered that building an additional water treatment plant to meet federal standards would cost between $8 and $10 billion, not including $ hundreds of millions in annual operations and maintenance costs. Protecting its water source had a much smaller price tag and would also enable the city to meet federal standards. To date, New York has invested more than $1.5 billion in watershed protection and improved the city’s water quality in the process.

The Urban Water Blueprint indicates that, out of the 534 cities analyzed, one in four would realize a positive return on investment from applying natural solutions to watersheds, including reforesting barren hillsides, protecting forested lands, improving regional farming practices, managing forest fire risk, or repairing stream and river banks. Return in this case is defined as avoided cost in treatment, suggesting many cities could save money today by investing beyond their municipal boundaries.

Savings from Farms to Faucets

Natural solutions can measurably reduce sediment and nutrient pollutants that flow into drinking water sources. The Urban Water Blueprint indicates that these solutions have the potential to improve water quality for more than 700 million people around the world. Watershed conservation at this scale would also save utilities approximately $890 million a year in avoided treatment costs.

To realize these savings, however, city and water managers need to expand their definition of urban water management to include source areas. In doing so, the importance of land use upstream of a city’s intake comes into sharp relief. Water quality is often degraded as forests are converted into cropland or ranchland, which increases sedimentation in water sources. The analysis reveals that this phenomenon is widespread, with two out of every five source watersheds experiencing significant forest loss over the past decade.

The Urban Water Blueprint indicates that the greatest potential to secure water for cities lies in improving the management of agricultural lands. To improve water quality for nearly 600 million city dwellers, cities would need to work with farmers to target agricultural best practices on some 16 million acres. That’s an enormous area—roughly the size of West Virginia—but also just 0.2 percent of the cropland area of watersheds. Accordingly, it is in science-based prioritization that conservation can be optimized for return on investment.

A Growing Track Record for Cost Sharing

When it comes to who pays for watershed conservation, size matters. For example, while New York draws most of its water from a watershed around 200,000 acres in size, Toledo draws its water from a watershed more than 169 million acres in size. Not unsurprisingly, the conservation action required to meaningfully improve water quality in these two cases varies dramatically.

For most cities, like Toledo, it is unlikely to be cost-effective for a water utility alone to pay the entire cost of watershed conservation. In these cases, cities should consider investing jointly with competing water users in a water fund—a process that establishes a multi-stakeholder financial mechanism to direct funds toward watershed conservation investments based on impartial science. The Nature Conservancy is now involved in more than 60 of these water funds where competing water users come together, often alongside a municipality, to invest in conservation upstream. In Santa Fe, N.M., for example, the city secured matching funds from the U.S. Forest Service to manage fire-prone forests in order to reduce the risk of forest fires that would likely leave their water reservoirs useless [5].

Cities have been able to monetize these extended benefits of watershed conservation. In Austin, Texas, for example, residents voted to protect the water quality of Barton Springs, a popular swimming hole that has become a beloved city landmark, with about 800,000 swimmers visiting every year. Since 1998, Austin has spent more than $145 million from voter-approved bond packages to buy and protect nearly 27,000 acres of environmentally sensitive land in and around the city [4].

Planning for a Sustainable Future

The Urban Water Blueprint report and accompanying data visualization website (www.nature.org/waterblueprint) provide a resource for decision-makers to evaluate urban water risks, the steps other cities have taken to overcome these risks, and the costs and benefits of incorporating natural solutions. The online tool was designed to be an engaging, interactive representation of the research and one that allows government officials and citizens alike to zoom in on any of the 534 cities. Each layer provides detail on the water challenges and conservation solutions for a city and each of its watersheds.
The report also outlines recommendations for cities, water utilities and partners interested in realizing the market potential of natural solutions. It lays out elements of a scale-up approach that includes suggestions for how to develop a reliable track record of delivery, monetize the value of watershed conservation and stimulate demand.

Great city leaders think about regional growth, not just city growth. In doing so, they define a route of development for both themselves and their neighbors in rural areas. The evidence is mounting for state and local officials to also extend their definition of urban water infrastructure to include the entire river systems and watersheds that their cities depend on and incorporating investment in those watersheds as part of their normal toolkit of securing water for people.

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